Surveillance of various enteropathogenic bacteria from diarrheal cases during 1989-1999 in Kobe City]

Incidence of various enteropathogenic bacteria was examined from diarrheal faecal samples that were collected from the patients of Kobe City General Hospital and some station hospitals (23,862), and from overseas travelers (2,855) over a period of decade (1989-1999) in Kobe. A total of 1,580 strains were isolated from domestic and 331 strains from overseas travelers. The results are as follows. 1) Thirteen kinds of enteropathogenic bacteria were isolated from domestic diarrheal cases (6.6%). Salmonella was the most predominant bacteria followed by Campylobacter, Vibrio parahaemolyticus, enteropathogenic Escherichia coli and Shigella. 2) Eleven kinds of enteropathogenic bacteria were isolated from overseas diarrheal travelers (11.6%). The most frequently isolated species was Salmonella, followed by Vibrio parahaemolyticus, Shigella and Plesiomonas shigelloides. 3) Of Salmonella strains isolated from domestic and overseas diarrheal cases, serovar Enteritidis was the most predominant. Other frequent serovars in both cases were Typhimurium, Tennessee, Hadar, Infantis, Blockley and Montevideo. 4) Antibiotics resistant rate of the isolated Salmonella strains was 42.6% for domestic samples and 29.3% for overseas diarrheal cases. In domestic cases. Enteritidis was resistance to streptomycin only and the multiple antibiotic resistance was observed in Typhimurium serovars. In overseas samples, the multiple antibiotic resistance was seen in a few Typhimurium, Anatum and Blockley strains. 5) Among Shigella, S. sonnei was isolated from both domestic and overseas cases. The frequency of acquiring infection was the highest in India, followed by Indonesia, Thailand and Nepal. 6) With reference to the incidence of the members of the genus Vibrio, Aeromonas and Plesiomonas, V. parahaemolyticus were abundant from domestic samples where as V. parahaemolyticus, P. shigelloides, Vibrio cholerae non-O1 and Vibrio cholerae O1 were isolated more frequently from overseas samples. The frequency of acquiring infection was the highest in Thailand, followed by Indonesia and India.     

Bacteriological studies of traveller's diarrhoea (6). Analysis of enteropathogenic bacteria at Kansai Airport Quarantine Station from September 4th, 1994 through December 1996

During the period of investigation from Sept. 4, 1994 to Dec, 1996, a total of 11,446,534 overseas travellers were quarantined at Kansai Airport Quarantine Station, and 22,187 voluntarily reported of episodes suffering from diarrhoea. Bacteriological examination of the stools a total of 9,299 individuals' was performed, and the following results were obtained. 1) Various enteropathogenic bacteria were isolated from 33.3% of the stools examined. Bacterial species isolated were as follows: Plesiomonas shigelloides, 2,066 cases (66.7%); Vibrio parahaemolyticus, 358 cases (11.6%); Aeromonas sobria, 360 cases (11.6%); Shigella spp., 291 cases (9.4%); Salmonella spp., 183 cases (5.9%); A. hydrophila, 126 cases (4.1%); and V. cholerae non-O1, 121 cases (3.9%). However, ETEC was not done with an object of test. 2) In 502 cases (16.2%), plural enteropathogenic bacteria were isolated from single patient, suggesting high frequency of a mixed infections. 3) From Feb. to Mar. 1995, thirteen cases cholera were found from patients who had travelled to Bali, Indonesia. Cases with enteropathogenic bacteria other than V. cholerae O1 were found without any seasonal variation. 4) The major regions where the travellers were infected with the pathogens are as follows: Vibrio spp., were from only Asia; Shigella, widely distributed but especially in India and Indonesia; P. shigelloides and Salmonella, widely distributed. 5) Among the Shigella strains, S. sonnei were isolated the most, followed by S. flexneri, S. boydii and S. dysenteriae. A strain of S. boydii provisional serovar E 16553 was isolated from a patient infected in India. 6) Among the Salmonella serovars, Salmonella Enteritidis was isolated the most frequently (49 cases, 25.7%). 7) 265 (89.2%) of 297 Shigella strains, 52 (27.2%) of 19] Salmonella strains, and 19 (95.0%) of 20 V. cholerae O1 were resistant to one or more drugs tested (SM. CP. TC. KM. ABPC. NA. OFLX). 8) All of the 20 V. cholerae O1 strains were Ogawa, E1 Tor. All of them were toxigenic strains. 9) The most frequently isolated serovar of V. parahaemolyticus was O3: K6. 89.8% of all V. parahaemolyticus strains were positive for thermostable direct hemolysin (TDH) gene, and 14.6% of them were positive for TDH-related hemolysin (TRH) gene by DNA-probe or PCR method.     

Antimicrobial resistance of bacterial pathogens associated with diarrheal patients in Indonesia

The antimicrobial susceptibility patterns for 2,812 bacterial pathogens isolated from diarrheal patients admitted to hospitals in several provinces in the cities of Jakarta, Padang, Medan, Denpasar, Pontianak, Makassar, and Batam, Indonesia were analyzed from 1995 to 2001 to determine their changing trends in response to eight antibiotics: ampicillin, trimethoprim-sulfamethoxazole, chloramphenicol, tetracycline, cephalothin, ceftriaxone, norfloxacin, and ciprofloxacin. Vibrio cholerae O1 (37.1%) was the pathogen most frequently detected, followed by Shigella spp. (27.3%), Salmonella spp. (17.7%), V. parahaemolyticus (7.3%), Salmonella typhi (3.9%), Campylobacter jejuni (3.6%), V. cholerae non-O1 (2.4%), and Salmonella paratyphi A (0.7%). Of the 767 Shigella spp. isolated, 82.8% were S. flexneri, 15.0% were S. sonnei, and 2.2% were S. dysenteriae (2.2%). The re-emergence of Shigella dysenteriae was noted in 1998, after an absence of 15 years. Shigella spp. were resistant to ampicillin, trimethoprim-sulfamethoxazole, chloramphenicol, and tetracycline. Salmonella typhi and Salmonella paratyphi A were susceptible to all antibiotics tested, while Salmonella spp. showed various resistance patterns according to species grouping. A small number of V. cholerae O1 were resistant to ampicillin, trimethoprim-sulfamethoxazole, chloramphenicol, and tetracycline; however, they were still sensitive to ceftriaxon, norfloxacin, and ciprofloxacin. Similar results were shown for V. cholerae non-O1. Campylobacter jejuni showed an increased frequency of resistance to ceftriaxone, norfloxacin, and ciprofloxacin, but was susceptible to erythromycin. This study shows that except for C. jejuni and V. parahaemolyticus, which appeared to be resistant to ciprofloxacin, the majority of the enteric pathogens tested were still susceptible to fluoroquinolones.     

Clinical trial of T-3262 on acute enteritis. Japan Research Committee of T-3262, Research Group for Acute Infectious Enteritis

For the purpose of evaluation of clinical efficacy, safety and usefulness on acute infectious enteritis (bacillary dysentery, and enteritis caused by Salmonella spp., Campylobacter spp., enteropathogenic E. coli, and so on), T-3262, a newly developed pyridone-carboxylic acid derivative, was administered to a total of 136 patients and carriers. In addition, in vitro antibacterial activity of T-3262 was determined against the clinical isolates, and compared with those of nalidixic acid (NA), pipemidic acid (PPA), enoxacin (ENX), norfloxacin (NFLX) and ofloxacin (OFLX). The daily dose of 450 mg of T-3262 was administered orally three times after meals for 5 days, with the exception of 7 day administration against Salmonella enteritis. A total of 89 cases were evaluated; 23 with Shigella spp., 30 with Salmonella spp., 15 with Campylobacter spp., 6 with enteropathogenic E. coli, and 15 cases with the other pathogens or pathogen-negative. The efficacy on clinical symptoms judging from duration of fever, and duration of diarrhea and abnormal stool character was 100% in all the enteritis except enteropathogenic E. coli enteritis, in which it was 50% (n = 2). Concerning bacteriological response, elimination of the causative organisms from the feces was 100% in Shigella spp. (n = 19), Salmonella spp. (n = 30), and enteropathogenic E. coli (n = 6), although 64.3% in Campylobacter spp. (n = 14). As an adverse effect, epigastric discomfort was observed in one (0.8%) of 130 cases. Deteriorations in laboratory findings were seen in five (6.2%) of 81 cases, consisting of two with elevated GOT and GPT, two with elevated GPT, and one with increased eosinophils count, although they were all slight in degree. MICs of T-3262 which inhibited 90% of the isolates of Shigella spp, Salmonella spp., and Campylobacter spp., were 0.025, 0.05, and 0.78 microgram/ml, respectively. These values were lowest among the quinolone derivatives tested, except that the MIC90 against Campylobacter spp. was the same as that of ofloxacin.     

Bacteriological study of traveller's diarrhoea. 4) Isolation of enteropathogenic bacteria from patients with traveller's diarrhoea at Osaka Airport Quarantine Station during 1984-1991]

During the last 8 years (1984 to 1991), 16,639,233 overseas travellers were quarantined at Osaka Airport Quarantine Station and 38,326 travellers reported that they were (or had been) suffering from diarrhoea. Bacteriological examination of stools from 12,573 persons revealed the following results. 1) Various enteropathogenic bacteria were isolated from 3,669 cases (29.2%) examined. The predominant species of bacteria isolated were as follows: Salmonella, 1049 cases; Plesiomonas shigelloides, 1030 cases; Vibrio parahaemolyticus, 789 cases; Shigella, 607 cases; enterotoxigenic Escherichia coli, 422 cases; Vibrio cholerae non-O1, 212 cases. 2) There were no apparent seasonal variations in the isolation rate of these pathogens. 3) The suspected regions for infection with these pathogens were as follows: a) Salmonella, Enterotoxigenic E. coli and Plesiomonas, mainly South-East and South-West Asia. b) Shigella, South-West Asia, especially India (59.8%). c) V. parahaemolyticus and V. fluvialis, mainly South-East and East Asia. d) V. cholerae non-O1, V. mimicus, almost restricted to Asia, mainly South-East Asia. 4) 22 strains of V. cholerae O1 were isolated and 19 were Ogawa, E1 Tor. Of these strains, 13 were cholera toxin-producing strains and 9 were non-toxigenic strains. 5) Several pathogens (mixed infection) were isolated simultaneously from 670 cases. 6) The 1247 Salmonella strains were identified into 98 serovars. 7) Of 624 Shigella strains isolated, 57.9% were S. sonnei, 29.2% were S. flexneri, 8.6% were S. boydii, 4.3% were S. dysenteriae. 8) The most predominant serovar of V. parahaemolyticus was O4:K8. Of 1,247 strains isolated, 9.8% were not producing thermostable direct hemolysin (TDH). 9) 570 (91.3%) of 624 Shigella strains and 409 (32.8%) of 1,247 Salmonella strains isolated were resistant to any one of the drugs tested (SM. CP. TC. KM. ABPC. NA. OFLX). The resistance rate and the number of multiple drug-resistance strains increased year by year. 10) Enterotoxigenic E. coli was isolated from 422 cases (10.7%) of 3,939 cases. Cases with enterotoxigenic E. coli strains producing ST (heat-stable), LT (heat-labile) or both ST and LT were 53.8%, 24.2% and 14.2% respectively. The others were cases with mixed types of enterotoxin production.     

Antimicrobial-resistant bacterial diarrhea in rural western Kenya

Bacterial diarrheal diseases cause substantial morbidity and mortality in sub-Saharan Africa, but data on the epidemiology and antimicrobial susceptibility patterns of enteric bacterial pathogens are limited. Between May 1997 and April 1998, a clinic-based surveillance for diarrheal disease was conducted in Asembo, a rural area in western Kenya. In total, 729 diarrheal specimens were collected, and 244 (33%) yielded >or=1 bacterial pathogen, as determined by standard culture techniques; 107 (44%) Shigella isolates, 73 (30%) Campylobacter isolates, 45 (18%) Vibrio cholerae O1 isolates, and 33 (14%) Salmonella isolates were identified. Shigella dysenteriae type 1 accounted for 22 (21%) of the Shigella isolates. Among 112 patients empirically treated with an antimicrobial agent and whose stool specimens yielded isolates on which resistance testing was done, 57 (51%) had isolates that were not susceptible to their antimicrobial treatment. Empiric treatment strategies for diarrheal disease in western Kenya need to be reevaluated, to improve clinical care.     

Incidence of bacterial enteropathogens among hospitalized diarrhea patients from Orissa, India

Bacteriological analysis of 1,551 stool/rectal swabs from all age groups of diarrhea patients of different hospitals of Orissa from January 2004 to December 2006 was carried out using standard procedures. Among all enteropathogens isolated in 886 culture-positive samples, Escherichia coli constituted 75.5%, including 13.2% pathogenic E. coli; Vibrio cholerae O1 constituted 17.3%; V. cholerae O139, 1%; Shigella spp., 4.5% (Shigella flexneri type 6, 2.9%, S. dysenteriae type I, 0.7%, S. sonnei, 0.6%, and S. boydii, 0.3%); Salmonella spp., 0.7%; and Aeromonas spp., only 2.0%. The isolation of bacterial enteropathogens was highest during July, 2005, followed by September, 2006. The prevalence of shigellosis in this region was relatively low. Cholera cases were more frequent during the rainy seasons. The dominance of V. cholerae O1 Inaba over Ogawa serotypes was observed in 2005, whereas this trend was reversed in 2006. The resistance profile of V. cholerae O1 was co-trimoxazole (Co), furazolidone (Fr), and nalidixic acid (Na); for Aeromonas spp., it was ampicillin (A), Fr, ciprofloxacin (Cf), Na, norfloxacin (Nx), and Co. Pathogenic E. coli strains were resistant to A, Fr, Co, streptomycin (S), Cf, Na, Nx, and neomycin (N); Shigella spp. were resistant to Fr, Na, Co, and S; and Salmonella spp. were resistant to A and Fr. Active surveillance should be continued among diarrhea patients to look for different enteropathogens and to define the shifting antibiogram patterns in this region.     

Epidemiology, etiology and pathophysiology of traveler's diarrhea

Traveler's diarrhea (TD) is the most frequent health problem in travelers to developing countries. Several personal and environmental risk factors are at the basis of TD acquisition and are discussed in this paper. TD is caused by a wide range of infectious organisms, ETEC and EAEC bacteria strains being the main enteropathogens incriminated in TD. Other causative bacteria are: Shigella spp., Campylobacter spp., Vibrio spp., Aeromonas spp., Salmonella spp., and Plesiomonas spp. Parasite species are also included: Cyclospora cayetanensis, Giardia lamblia, Cryptosporidium, Entamoeba histolytica, as well as viruses: rotavirus, adenovirus, Norwalk virus. Due to the great diversity of pathogens incriminated, several pathophysiological mechanisms have been described and some of them are still poorly understood. The clinical symptoms present are also quite variable, although inflammatory and non-inflammatory diarrhea have been established as a classical and basic classification of diarrhea.     

Isolation of enteropathogenic microorganism from patients with infection of the digestive tract during 1976 to 1988 in Tenri Hospital]

Enteropathogenic microorganisms isolated from feces of 9,393 patients with diarrhea or enteritis in our hospital between 1976 and 1988 were analyzed. As the result of the examination of 5,443 outpatients, 1,811 strains of pathogens were isolated from 1,686 cases (31.0%). Several species including Salmonella spp., Escherichia coli serotype, Vibrio parahaemolyticus, were isolated before 1978, and the incidence of pathogens was low (14.8%). For the 10-year period since 1979, the incidence markedly increased to 34.4%, and the number of pathogens isolated also increased to about twice that before 1978. The main cause of the increase was Campylobacter species. The major pathogens detected since 1979 were Campylobacter spp., E. coli serotype, Salmonella spp., V. parahaemolyticus, etc., but Rota virus, Clostridium difficile, Aeromonas spp., Vibrio fluvialis, etc. have also been detected, showing an increase in the number and diversity of the detected pathogens. As the result of the examination of 3,950 inpatients, 835 strains of pathogens were isolated from 800 cases (20.3%). The incidence of C. difficile was the highest, 423 of 800, followed by E. coli serotype, Salmonella spp., Campylobacter spp., V. parahaemolyticus and Aeromonas spp., in that order. All the inpatients from whom C. difficile was isolated manifested diarrhea or enteritis after administration of antimicrobial agents. The pathogens causing communicable disease were Salmonella spp. serovar Typhi, Salmonella spp. serovar Paratyphi A, Shigella flexneri, Shigella sonnei and Entamoeba histolytica, which were isolated from 5, 1, 3, 2 and inpatients, respectively.     

The seasonal variation in the microbial agents implicated in the etiology of diarrheal diseases among children in Lao People's Democratic Republic

During 1994-1995, the etiological structure of children's diarrhea was monitored in outpatients at Mahosot Hospital, Vientiane, Lao PDR. Of the 191 children studied, 42% had stool specimens positive for enteropathogens; 22% had rotavirus, 21.5% enteropathogenic E. coli, 4.7% Shigella flexneri, 2.9% Campylobacter jejuni, 2.1% Shigella sonnei, and 0.5% each of Giardia intestinalis and Entamoeba histolytica. No Vibrio cholerae and Salmonella spp. was detected in this monitoring. In children under five years, rotaviruses were detected almost all round the year with a maximum prevalence in January in the dry season. Shigella species were highly detected in June to July in the rainy season.     

Bacterial enteric pathogens in children with acute dysentery in Thailand: increasing importance of quinolone-resistant Campylobacter

Current data on pathogen prevalence and drug resistance patterns are important for treatment and vaccine-development strategies. An etiologic study of acute bacterial dysentery was conducted in children up to 12 years of age in 2 major hospitals in and around Bangkok. Stool samples or rectal swabs and clinical data were collected. Standard microbiological methods were used to detect Salmonella, Shigella, Campylobacter, Vibrio, Aeromonas and Plesiomonas. Pathogenic E. coli (ETEC, EIEC, STEC) was identified by digoxigenin-labeled probes. A total of 623 cases were enrolled: median age 11.0 months (range 1 month-12 years). At least one bacterial pathogen was isolated in 55% of cases. Campylobacter was the most common pathogen found (28%), whereas Salmonella, Shigella and ETEC were isolated from 18%, 9% and 6% respectively. EIEC, Vibrio and Plesiomonas were isolated from <1% and no STEC was detected. C. jejuni serotypes 36, 4 and 11 were the most common. The mean age of cases with Campylobacter was significantly lower than with Shigella (17.9 vs 52.8 months, p<0.001). Clinical presentations of Campylobacter and Shigella infections were compared: fever (28% vs 37%), abdominal colic (62% vs 80%, p<0.05), vomiting (38% vs 70%, p<0.001) and bloody stools (52% vs 48%). The Campylobacter isolates (80% C. jejuni, 20% C. coli) were 90% resistant to ciprofloxacin but sensitive to macrolides. All the Shigella isolates (70% S. sonnei) were sensitive to quinolones. Our study illustrates the increasing importance of quinolone-resistant Campylobacter and the decline of Shigella in the etiology of dysentery in Thailand. The clinical presentation of campylobacteriosis is similar to that of shigellosis, except that the patients may be younger and there may be less association with colic and vomiting; having fecal leukocytes will be >10/HPF. The use of macrolide antibiotics rather than quinolones would be reasonable in children <24 months of age; fluoroquinolones will be ineffective in at least half of culture-positive cases.     

In vitro antimicrobial activity of rokitamycin, a macrolide antibacterial agent, against clinically isolated strains of Campylobacter and other enteritis-causing bacteria]

We determined the minimum inhibitory concentrations (MICs) of rokitamycin (TMS-19-Q, RKM), a macrolide antimicrobial agent, against strains of various bacterial species isolated from enteritis patients, and compared them with those of josamycin (JM), erythromycin (EM) and ofloxacin (OFLX). MIC90 of RKM against 147 strains of Campylobacter jejuni, and each 25 strains of Shigella spp., Salmonella spp. and diarrheagenic Escherichia coli were 1.56, 200, 800 and 200 micrograms/ml, respectively. There was only one RKM resistant (MIC greater than 100 micrograms/ml) C. jejuni strain, while most of the strains of the other species were resistant to RKM. MIC values of the other drugs were all similar to those of RKM. MIC90 of OFLX against 147 strains of C. jejuni was 0.78 micrograms/ml, lower than other drugs.     

The role of Shigella spp., enteroinvasive Escherichia coli, and other enteropathogens as causes of childhood dysentery in Thailand

Shigella spp. were isolated from 44%, Pleisomonas shigelloides from 22%, Campylobacter spp. from 16%, and Salmonella spp. from 10% of 200 Thai children with mucoid or bloody diarrhea. Enteroinvasive Escherichia coli (EIEC) was identified by examining isolates of E. coli for plasmids larger than 120 megadaltons (MDa), by identifying E. coli with a virulence marker antigen in an ELISA, and by performing DNA hybridization with a 17-kilobase (kb) EcoRI digestion fragment of plasmid pWR100 (a 140-MDa plasmid of Shigella flexneri 5). Sixty-four isolates of EIEC from 10 (5%) of the children were identified by these methods and confirmed by the Sereny test. All isolates of EIEC fermented lactose, and isolates of EIEC from seven children belonged to recognized serotypes of EIEC (O28ac:H- and O29:H-), whereas isolates of EIEC from three children were untypable. Examination of DNA from the total fecal growth with the 17-kb probe identified 9 of 10 children from whom EIEC were isolated and 2 of 102 children from whom EIEC or Shigella spp. were not isolated. Detection of EIEC by ELISA and DNA hybridization are important advances in defining the etiology of dysentery.     

Detection and identification of bacterial enteropathogens by polymerase chain reaction and conventional techniques in childhood acute gastroenteritis in Gaza, Palestine.

BACKGROUND: Acute gastroenteritis and diarrhea are common and costly problems that cause significant morbidity and mortality in children worldwide. In Palestine, diarrhea is one of the major causes of outpatient visits and hospitalizations. METHODS: To improve knowledge on the etiology of gastroenteritis and diarrhea in our patient population, stool specimens from 150 children under 5 years of age suffering from acute gastroenteritis were investigated for various common bacterial enteropathogens by conventional and molecular techniques. RESULTS: Bacterial enteropathogens were detected in 17.3% of the diarrheal samples. Shigella spp was the most common bacterial pathogen (6.0%), followed by Campylobacter coli/jejuni (4.7%), Escherichia coli O157:H7 (4.7%), and Salmonella spp (2.0%). Shigella and Salmonella isolates were tested for their susceptibility to common antimicrobial agents and most of the Shigella isolates were resistant to ampicillin, trimethoprim/sulfamethoxazole and doxycycline and most of the Salmonella isolates showed resistant to ampicillin, trimethoprim/sulfamethoxazole, doxycycline and nalidixic acid. CONCLUSIONS: The results highlight the value of using a combination of traditional and molecular techniques (PCR) in the diagnosis of bacterial gastroenteritis. Furthermore, this study demonstrated that E. coli O157:H7 and Campylobacter, which are not screened for routinely in the Gaza Strip, were significant enteropathogens.     

Acute diarrhea due to enteropathogenic bacteria in patients at hospitals in Tehran

During a study examining causes of diarrhea from May 2004 to May 2005, 808 stool specimens were collected from patients with acute diarrhea in Tehran. Fecal samples were cultured and identified according to the standard biochemical methods. Molecular identification of enteropathogens was carried out by amplification of their virulence genes by polymerase chain reaction. A total of 369 (45.6%) bacterial pathogens were recovered from 808 patients as follows: Shigella spp., 155 (45.6%); diarrheagenic Escherichia coli 143 (38.8%); Salmonella spp., 51 (13.8%); and Campylobacter spp., 20 (5.4%). Most of the diarrheagenic E. coli were Shiga toxin-producing E. coli, with 64 (44.7%) isolates, followed by 47 (32.9%) enterotoxigenic E. coli isolates; among Shigella spp. isolates, 69 (44.5%) Shigella flexneri were predominant. The molecular diagnosis of enteropathogens yielded a more accurate characterization of the prevalence of diarrhea-causing bacterial strains in Iran. The present study revealed a high prevalence of Shigella and diarrheagenic E. coli as the predominant causes of bacterial diarrhea in this region of the world. These two types of bacteria should therefore be considered when designing preventive strategies for people living in Iran.     

Prevalence of Campylobacter jejuni and enteric bacterial pathogens among hospitalized HIV infected versus non-HIV infected patients with diarrhoea in southern India

A prevalence study on Campylobacter jejuni and other enteric bacterial pathogens was carried out in 200 HIV infected and 200 non-HIV infected subjects with diarrhoeal symptoms at an AIDS Hospital in southern India. Diarrhoeal specimens were inoculated onto standard culture media as well as onto Columbia and Campylobacter blood agar media for C. jejuni isolation. All the C. jejuni isolates were tested for antimicrobial susceptibility using Kirby-Bauer's method. A significant difference in recovery rates was observed between the 2 groups in relation to C. jejuni (p < or = 0.02; 95% CI 5.5 (1-10) and Shigella spp. (p < or = 0.02; 95% CI 6.5 (1-12). 21 isolates of Shigella spp., 16 C. jejuni, 5 Salmonella typhi, 3 Arcobacter spp., 3 Yersinia enterocolitica, and 2 Aeromonas hydrophila were recovered from the HIV infected cases. All the C. jejuni isolates were sensitive to ciprofloxacin whereas 1 strain was resistant to nalidixic acid. Interestingly, all the 29 Shigella spp. (21 from HIV and 8 from non-HIV cases) were resistant to erythromycin and most were resistant to many other antibiotics used. Our observations underline the need for epidemiological investigations to screen C. jejuni and Shigella spp. in HIV infected subjects with diarrhoea and analyse their antibiograms periodically to minimize disease burden in HIV/AIDS.     

Bacteriological survey of diarrheal epidemics in the 1998 Bangladesh floods]

In 1998, the worst flood disaster in Bangladesh ravaged more than half of its land and diarrheal epidemics broke out. We examined fecal specimens of diarrheal patients at rural hospitals in Chandpor district located 140 km southeast of Dhaka to analyze the enteric bacterial pathogens in post-flood period October. Of the 76 patients stools examined, Vibrio cholerae O1 biotype El Tor, serotype Ogawa, and Vibrio cholerae O139 Bengal were detected in 25 (33%) and in 14 (18%) respectively. Other enteropathogenic bacteria confirmed were Vibrio cholerae O5, Vibrio fluvialis and Enteropathogenic Escherichia coli O44. Neither Shigella nor Salmonella species was detected in this study. A drug susceptibility test was performed using TC, DOXY, CPFX, NA, and AMPC disks to cholera Vibrios. The O1 Vibrios showed the same susceptible pattern as O139 excluding NA susceptibility. TC resistant strain among the Vibrios was not detected though TC is a common therapeutic drug for diarrhea in this area. Our result clearly suggested that the epidemic potentiality of O139 still existed in rural Bangladesh.     

Enterotoxigenic Escherichia coli causing cholerogenic syndrome during an interepidemic period of cholera in North India

A study was undertaken to look for heat-labile enterotoxin producing Escherichia coli (LT-ETEC) in patients with acute watery diarrhea resembling cholera in Chandigarh in North India. Two periods were selected, an interepidemic (2001) and an epidemic (2002) period. Heat-labile enterotoxin (LT) was detected using reverse passive latex agglutination test. LT-ETEC strains were serotyped and antimicrobial susceptibility was studied. LT-ETEC was detected in 16 of 21 stool samples during 2001.Other organisms isolated included Vibrio cholerae O1 Ogawa and Aeromonas hydrophila in 2 and 3 patients, respectively. During the epidemic period, 4 of 17 samples tested positive for LT-ETEC, whereas V. cholerae, Shigella, and Salmonella were isolated in 91, 2, and 1 patient, respectively. Similar features such as acute watery diarrhea and dehydration were common to patients examined in the interepidemic period and those examined during the cholera epidemic. The serotypes isolated were O15 (8), O63 (2), O148 (2), and O158 (2), and the remaining strains were untypable. More than 50% of patients were adults. Antimicrobial susceptibility was as follows: amoxycillin (3/20), nalidixic acid (6/20), trimethoprim (5/20), chloramphenicol (8/20), amikacin (19/20), gentamicin (13/20), cefotaxime (15/20), and ciprofloxacin (10/20). High fluoroquinolone resistance in ETEC may be a serious cause of concern for travelers visiting this region, and thus thereis a need to monitor drug resistance in this pathogen.     

Comparative value of colonic biopsy and intraluminal fluid culture for diagnosis of bacterial acute colitis in immunocompetent patients. Infectious Colitis Study Group.

We compared the yield of intraluminal fluid culture to that of biopsy specimens obtained during colonoscopy for the diagnosis of bacterial colitis in 93 immunocompetent patients with a recent episode of diarrhea and macroscopic lesions of colitis. Stool culture findings were also available for 68 patients. At least one bacterial pathogen was isolated from the biopsy specimen, intraluminal fluid, or stool from 48 patients (51.6%). Salmonella species, Clostridium difficile, Klebsiella oxytoca, Shigella species, and Campylobacter species were recovered from 16 (17.2%), 15 (16.1%), 8 (8.6%), 7 (7.5%), and 4 (4.3%) of the patients, respectively. One Shigella species and one K. oxytoca strain were isolated from biopsy specimens but not from intraluminal fluid, and intraluminal fluid was the only positive specimen in 12 cases (yielding 1 Salmonella species, 2 Shigella species, 2 K. oxytoca, and 7 C. difficile isolates). In nine cases out of 10, toxin B was detected only in intraluminal fluid. A correlation of 91.2% was observed between stool and intraluminal fluid cultures for Salmonella, Shigella, and Campylobacter species isolations. Culture of biopsy specimens adds little to the diagnosis of infectious colitis, and stools and intraluminal fluids appear to have comparable value.     

Etiology of acute diarrhea among children in Ribeirão Preto-SP, Brazil

To study the main enteropathogens causing diarrhea in the region of Ribeir?o Preto regarding serogroups and serotypes, the feces of 1836 children under 10 years old, from both sexes, attack of acute gastroenteritis, were analysed during a period of 4 years in Adolfo Lutz Institute - Ribeir?o Preto, SP. The pathogens identified by standard methods were the following: Escherichia coli, Salmonella spp., Shigella spp., Campylobacter spp., Yersinia spp., and Cryptosporidium spp. Positive samples were 22.8% (419) with 1.7% association of pathogens. Larger isolates were mainly from children 0 to 11 months old. Enteropathogenic E. coli (EPEC) was most frequent (8.7%) with predominance of serogroup O119 (40.2%), followed by Shigella (6.2%), 63.6% of which S. sonnei.